Mechanism of lithium battery

　　Lithium ion batteries use carbon materials as negative electrodes and lithium containing compounds as positive electrodes. There is no metal lithium, only lithium ions. This is called lithium ion batteries. Lithium ion battery is a general term for batteries with lithium ion intercalated compounds as cathode materials. The charging and discharging process of lithium ion battery is the process of lithium ion embedding and de embedding. In the process of lithium ion insertion and deinking, the insertion and deinking of equivalent electrons with lithium ion are accompanied at the same time (traditionally, the positive electrode is indicated by insertion or deinking, while the negative electrode is indicated by insertion or deinking). In the process of charging and discharging, lithium ions are inserted/de inserted and inserted/de inserted back and forth between positive and negative electrodes, which is vividly called "rocking chair battery".

　　When the battery is charged, lithium ions are generated on the positive pole of the battery, and the generated lithium ions move to the negative pole through the electrolyte. The carbon as the negative electrode has a layered structure, which has many micropores. The lithium ions reaching the negative electrode are embedded into the micropores of the carbon layer. The more lithium ions are embedded, the higher the charging capacity. Similarly, when the battery is discharged (that is, the process of using the battery), the lithium ion embedded in the carbon layer of the negative electrode is removed and moves back to the positive electrode. The more lithium ions returned to the positive electrode, the higher the discharge capacity.

　　Generally, the charging current of lithium battery is set between 0.2C and 1C. The higher the current is, the faster the charging is, and the higher the battery heats up. Moreover, the capacity is not full when charging with excessive current, because the electrochemical reaction inside the battery takes time. Just like pouring beer, pouring too fast will produce foam, but dissatisfaction.

　　Precautions for use (discharge)

　　For batteries, normal use is the process of discharging. Pay attention to the following points when discharging lithium batteries:

　　First, the discharge current should not be too large. Excessive current will cause internal heating of the battery, which may cause permanent damage. On mobile phones, this is not a problem and can be ignored.

　　Second, over discharge is not allowed. The internal storage of electric energy of lithium battery is realized by a reversible chemical change of electrochemistry. Excessive discharge will lead to irreversible reaction of this chemical change. Therefore, the lithium battery is most afraid of over discharge. Once the discharge voltage is lower than 2.7 V, the battery may be scrapped. Fortunately, the cell phone battery has been installed with a protection circuit, and the voltage is not low enough to damage the battery. The protection circuit will work and stop discharging.

Read recommendations:

5/AA USB 1.5V 2035mWh

Several misconceptions about lithium battery maintenance!18650 battery 3.7v 2200mah

Graphene battery technology principle.lithium battery energy storage Processing

energy storage system lithium battery Product

18650 battery pack Processing